Scaffold structure for use in tube nest manufacture



SCAFFOLD STRUCTURE FOR USE Nov. 29, 1949 w, HUBER 2,489,889

IN TUBE NEST MANUFACTURE Original Filed July 3, 1945 3 Sheets-Sheet l INVENTOR Wa/fer Huber ATTORNEYS 29, 1949 w. HUBER 2,489,889

SCAFFOLD STRUCTURE FOR USE IN TUBE NEST MANUFACTURE Original Filed July 3. 1945 3 Sheets-Sheet 2 o I l I 10 III ATTORNEYS Nov. 29, 1949 w. HUBER SCAFFOLD STRUCTURE FOR USE IN TUBE NEST MANUFACTURE Original Filed July 3, 1945 3 Sheeis-Sheet s INVENTOR ATTO R N EY$ Patented Nov. 29, 1949 PAT E 21 489,885 SGA'FFOLD STRUGTURE'FOR USE-'IN-TUBEI NES'III'MAN'UFKGTURE Walter Hat r, wifitei'thur, Switzerland, assigii n t9. Sulz'ei Freies, Sbbiete A'I'mnym'e, wWinteithul,

Switzerland e new .u si nt'embbf, 23, 194,41.

Se! LNo. 790,798; Inlswitzerlande 7" (Elaimsz (01; 113 -99 The invention desc'ribeeianaeiarmee lates to seaffqlcling structure tof assist in the-as sfehibly of tube nests, particularly nests* assem:

lffl'ed" according in a inethed ef-' cqnstyu nest ofyparallel' tubes; which are supp H H each other bywelde'd'bfidges'andaie a aeh'ed at beth ends to tube end wane as diselesed and elaimedjn' my cqpfen'di'rig applicant-1,; senat Nd: seem-4, filed July 1-945, of Whieh" this is a division. Y Themethod (if the parentinvention-ebnsistsfin that the tube end walls and-thetubes' a ref held bya template scaffelding dui'ingPthe ins'extion of --th' biidges seine or all OfTithetubes-WhieH-aie' heated by welding being;cooled means of -a' cooling medium, while Siameor} en es the tubesdnl'g slightly or not at an "arm-ed by w lding; ar heated by means of anemmgmeamm; In this Way-the effect can be" obt'aihed that durin the manufacture of "a nest any wa'rpiii'gf-the nest due to non-unifei'nrheating and thetresses arising therefrom canbe cOmp l'etely-avbidedi For carrying" outtheforegoing--r'r'1etl:i0d*a? ear: folding acee'r'dih'g to'the present inventibn e'an be pibvided on which teihplateskare attachedev rhich' Hold the" tubes at-least' over part ofthe cir'cuxhti fer ence' of" the nest and the tubeehd WaIIs'iin thqf position correspondingto thedesi'gnofi the? nest:-

Bbtnthe cooling medium: ahe' the heating med-mm are preferably conducted: thrbug h: thet'iibes of the nest. During-welding itself, it: is advisable to interrupt the fiow of ceqling-medium' through the tube on "which Welding is being denez" Between the cooled and-- the heated tubes the" tubes ofat least one layer may centain a medtumwhich neither absorbs 1101' gives off heat; Oran} insulating substance may be pressed into-them The manufacture of the" tube nest may be f'aciliei tatedby setting the tubes betweenwhieh bridgesf are to be made at the rightdistance frq n earth other by means of Wedges before thebrid'ges-rare made.

If three or more welded bridges are prdvidedw foi a single tube, itis advisa'ble'towarrangegthe" iilates may be attaehedwhich Z v gang d m the fegien p th'e; sat s 1;?1 theitebele'rfid walls by means of a pressure medium. introdued into'the interi'oi of the tubes.

. the i i o ap l in t inyentiei i tih e i i t e e 1 at; leasta art oftheeifquin erehee o-f the ne st a q re held by the se o qir'ig. It is: @150- sib 1 o; template lqamsi. tq be pfeviaed \thi'ii have ppening's to fit t tubes of. awn-e19: layei re-e t mpla e. sesame; p' i abl i I ha w t side svofth'eitube ,nes'ts, p narsitogwmeh' the teih plate beams] and templates, earl. be, attah'e'di These latei nail pillars mayi ave a i613 allow" theitemplate bea'rhs toI be" fixuias desired at different heights;v the g ahel-tufes tcdli'espbhding td' t e positions of the single: t be leyersi bis-v tributing' and" collecting casi' subhlfin g and leading o the heating may lse be nibvably -laid', en the tubefl diwaiils oni beuisgaesl mgvable' distributing pipe {may alsoj bbrdxiide d gr up ing h 911 5 Med m! a qf'lfbn'i t i 5 49 m i sm l a t et a eats e a pi at 5 w: one le e Q thwfi t... ii ex ed nt w 12 thesesupply pipes t9 beprovided with closing; n ernbe sthrough hiqh the; supply of cooling ma ame h 'li e ietli afi t an e n l rupted fo r instance du ring the insertibn ofthe: welding bridges. A movable distributing pipe ma also be provided for the: pressure, medium usedfor detecting leakages- 4nd from this epipe supply pipes-lead to thec;si-ng1e, tubes of at'least ne layer; of thenestz: The-supply? pipes: may have ati the; endintroduce'd into the tubes of the nest; sealing'imeans Wihichaare pressed against the-tube; surface by ;the pie'ssure of the-pressure 'mediumasupply itself: At the ends of' 'thetubes" opposite to the ends connected :tothe distributing pipefor- 'pres'sure medium; s'tepper'sm'ay be 15%- vided" whichsealithe' tubes i at this end;

bridges of one tube layer in staggered fashion in; cordin'g to theinvention:

suc'ha way that not all of: them'are applied to-t onetube at the same time, further bridges being} simultaneously applied to neighboring tubeS-iQfi the" same layer-u The tubes of twoirieighboring layers may be inspected fonleakage's byhieahs-ofi scale;

apr'es'sure medium before a further; layer 'is-supportedon one ofthe'first two layers. Whemthefi bridges have beentmade, the'tubesimayhe fixed,"

for instance by inserting them intothe-tube'rend' Fig. 5s'hoW's th a still larger" scalethe appliea tion of. wedges name-ensure thea flghtedistan'ee between t'ub esj;

Fig: 6: shbWs the insertion" ofsingle welded walls; When thisis donethetubes 'may'be ex w bridges;

Fig. '7 shows the nest of tubes from above with the arrangement for detecting leakages; and

Fig. 8 shows on a larger scale a part of the arrangement employed for supplying pressure medium in the leakage test.

For constructing the nest of tubes a template scafiolding is employed which has three longitudinal beams I, 2 and 3, by which the lateral pillars 4 and 5, the underlying supporting templates 6 and finally the overlying spacing template beams l' are held in place. At the ends of the template scaffolding supporting and positioning templates 8 and 9 are attached, and in these the tube end walls l and H respectively are inserted. During the insertion of the welded bridges the tubes l2 and the tube end walls ill and II are held in the position corresponding to the design of the nest by this template scafiolding. A cooling medium is meanwhile supplied through a distributing .pipe I3 to some of the tubes which are heated by welding, while other tubes, which are only slightly or not at all warmed by the welding are heated by a heating medium supplied through the distributing casing M.

It is appropriate to employ as cooling medium air from the atmosphere which is introduced into the distributing pipe l3 through the pipe l5 by means of a supply device not shown in the drawing. From the distributing pipe single supply pipes is lead into the tubes of the top layer requiring to be cooled. In order to enable the supply of cooling medium to be interrupted temporarily, for instance during the insertion of the welded bridges between the tubes, closing members ll are also provided in the supply pipes l6.

Air also serves as heating medium, being introduced into a heatin device IS with the aid of a fan 18 and conducted in a heated state through the pipe 29 into the distributing casing 14. It is expedient for the pipe 29 to have articulated joints not shown in detail in the drawings, in order to enable the position of the casing M to be continually adapted to the stage which the construction of the tube nest has reached. After the heating medium has flowed through the lower layers of the nest of tubes I2, it is collected by the casing 2| and returned to the fan 18 through the pipe 22, which is also equipped with articulated joints.

The design of the lateral pillars 4 and 5, the templates 6 and the template beams I is shown in detail in Fig. 4. The templates 6 have the form of a part of the circumference of the tube nest under construction. The outermost tubes of the nest are introduced into the indentations of this template. The template beam 1 also has indentations corresponding to the distance between the tubes of one tube layer.

With the aid of bolts inserted in the apertures 23 in the pillars 4 and in apertures of the template beam 7 the latter can always be kept in the position which corresponds to the layer of tubes inserted at the top. In order to secure the right distance between the tubes l2b already welded (Fig. 5) and the tubes l2a not yet provided with welded bridges, wedges 24 may be driven between these tubes and press the tubes [2a tight into the indentations 25 of the template beam 1'.

For making the welded bridges the tube layer I2a not yet welded is cooled with the aid of the cooling medium. The layer of tubes lZb contains stagnating air which neither absorbs nor gives off heat. The lower layers I20, however, have heating medium flowing through them. If

necessary an insulating material, for instance as-' bestos sheeting, asbestos or glass wool, may also be introduced between the tube layers I211. and [21) or I21) and I20. The insertion of the welded bridges begins in the centre of the tube layer and at first only'the welded bridges 26a (Fig. 6) in the middle are made. When these bridges have been completed the welded bridges 2% are made at the same time on the same and the neighboring tube in staggered fashion. When these have been completed, the welded bridges 260 are simultaneously made. Then follow in a further simultaneous working process the weld points 2601, etc., in staggered fashion until the welded bridges are made up to the outer circumference of the nest of tubes. Obviously, during the insertion of the welded bridges in the direction running from the middle to the one side, the welded bridges from the middle to the other side are made at the same time and in the same staggered fashion. In the staggered production of the welded bridges described only two bridges are made at the same time on each tube.

The welded bridges can be produced by autogenous welding. In the process the welder preferably moves with the burner towards the flame so that the part of the tubes to which metal is applied is already preheated by the front end of the flame, while at the same time the danger of the newly applied material flowing away behind the flame is considerably diminished. During the insertion of the Welded bridges the cooling-air supplied to the tube on which the bridge is being made is interrupted. Thus, according to the staggered application of the welded bridges, the cooling air supplied will be interrupted in a small number of adjacent tubes in the layer. When all the Welded bridges have been applied to a tube the cooling air supply is again opened. When all the welded bridges have been applied to a Whole layer of tubes, the tubes of this layer are affixed to the tube end wall by being expanded at both ends. The expansion can be done for instance with the aid of known tube headers or tube expanders. It is also possible, however, for a medium at high pressure to be introduced into the interior of the tube and for the tubes to be expanded by this and thus firmly fixed in the openings of the tube end walls.

When the welded bridges have been applied to all the tubes of two layers l2a, [2b, the tubes of these layers are tested for leakages. For this purpose a pressure medium i supplied by a pressure pump through the pipe 2? (Fig. 7) to the distributing pipe 28, this medium being conducted to the tubes of one tube layer through the supply pipes 29. On the other side the ends of the tubes are sealed with the aid of plugs 3i! and a bridge piece 3|, so that the tubes under pressure can be tested for leakages. The distributing pipe 28 (Fig. 8) has single connections 32 whose distance from each other corresponds to the distance between the tubes of one layer and in which either a blank pin 33 or a supply pipe 29 can be inserted as required. Th supply pipe 29 has a sealing means 3 t which is pressed against the tube with the aid of the ring 35 by the pressure of the pressure fluid itself. The closing plugs are similarly designed with the sole difference that they are not hollow, so that the tube to be tested is sealed from the outside.

made of the same metal as the tubes, or of a similar metal. Metals of other types, however, may also be employed in so far as they can be alloyed with the metal of the tubes at the point of connection. For this purpose additional substances may be employed which ensure good fluid fusion. The bridges may furthermore be formed by solid pieces of metal laid between the tubes and Welded to them.

I claim:

1. A. scaffold structure to assist in the assembly of tube nests including in combination, a base, supporting templates affixed to said base ar ranged to underlie a tube nest being assembled and having spacing means for holding a portion of the peripheral tubes of said nest, overlying templates adjustably carried on said base and having spacing means for holding one layer of the tubes of said nest, a pair of supporting and positioning templates affixed to said base and arranged to hold the tube end Walls in final, assembled space relation to the tubes of said nests, a distributing and a collecting casing at opposite ends of said structure outside of and movable across said end walls arranged to deliver and receive respectively a heating medium to and from a plurality of tubes of said nest, a second distributing casing at one end of said structure outside of and movable across the adjacent end wall, and individual supply pipes leading from said second casing to the single tubes of at least one layer of said nest for th supply of a cooling medium thereto.

2. The combination of claim 1 in which the individual supply pipes are individually provided With closing members therethrough.

3. As a sub-combination in a scaffold structure to assist in the assembly of tube nests, a base, a pair of pillars afiixed to said base to rise on opposite sides of the tube nests being assembled thereon and an overlying template beam adjustably carried on said pillars having tube spacing means on the underside thereof, said pillars havfor interrupting the flow ing apertures for fixing said template beam at various heights as desired, the spacing of which apertures corresponds to the spacing of single successive tube layers in the nest to be assembled.

l. The combination of claim 3 in which an underlying supporting template having tube spacing means on its upper side is afiixed to the pillars said tube spacing means bein arranged to engage the exterior tubes of the lower half of the tube nest being assembled in their final assembled position.

5. As a sub-combination in a scaffold structure to assist in the assembly of tube nests, a base, spaced means carried by the base for receiving and supporting tube end walls in openings therein, means carried by the base for supporting tubes in their spaced, final relation to the end walls, a manifold having a width at least substantially as great as the width, in one direction, of the nest of tubes of the completed tube nest, said manifold being movable across and closely adjacent the outer face of one of the end Walls so supported to provide a flow connection for heat-transmitting fluid through pre-selected tubes being assembled in the nest.

6. The sub-combination of claim 5 which also includes a manifold to supply fluid to the individual tubes of at least one layer of the nest through individual supply pipes.

7. The sub-combination of claim 6 in which each individual supply pipe is provided with a cut-off.

WALTER HUBER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,660,576 Owston Feb. 28, 1928 1,852,180 McKnight et a1 Apr. 5, 1932 2,332,368 Burtenshaw Oct. 19, 1943 

